Screw



(No Model.)

J. ERICSON. SCREW.

No. 429,851. Patented June 10, 1890.

UNITED STATES PATENT OFFICE."

JOHN ERICSON, OF SABINE PASS, TEXAS.

SCREW.

SPECIIEIGATION forming part of Letters Patent No. 429,851, dated June 10, 1890. Application filed February 19, 1890. Serial No. 340,981. (No model.)

To all whom, it may concern:

Be it known that I, JOHN ERICSON, a citizen of the United States, residing at Sabine Pass, in the county of Jefferson and State of Texas, have invented a new and useful Screw, of which the following is a specification.

This invention has relation to screws for use in wood-working; and among the objects in view are to provide a screw adapted to be inserted through thin sections of wood, and near the edges thereof, without liability of splitting the Wood, and this without the necessity of any previous boring to form an opening or receptacle for the same. In other words, the main object of my invention is to provide a screw constructed and adapted to form the opening for its own reception.

With the above objects in view the invention consists in a screw having a straight shank and body of similar diameters throughout their combined length, and in providing the shank and body with a longitudinal strc ight groove or channel terminating at its lower end or at the terminal of the shank in what may be termed a gouge-bit.

Referring to the drawings, Figure 1 is a side elevation of a screw constructed in accordance with my invention, looking toward the channel. Fig. 2 is a similar view looking at the screw at a point slightly to the right of the channel. Fig. 3 is a longitudinal section through the channel. Fig. 4: is a transverse section through the shank. Fig. 5 is a detail enlarged view of the end of the screw.

Like numerals of reference indicate like parts in all the figures of the drawings.

The screw comprises the usual shank, body, and head, designated by the numerals 1, 2, and 3, respectively. The head is of the ordinary construction, and the shank and body are of the same relative diameter throughout their combined lengths, the shank being provided with the usual threads 4.

Extending from the juncture of the head with the body of the screw to the enteringpoint of the shank is a channel5, perfectly straight throughout its length and parallel to the longitudinal axis of the shank and body. The terminal of the shank were it not for this channel would be rounded and of a semi-spherical shape; but by the channel a portion of the terminal is removed, leaving a sharp entering-point similar to an ordinary gouge bit or chisel, as shown at 7. The edges of the groove or channel are of course sharp and cut their way into the wood, thereby forming an entrance for the shank and body, the shavings being fed upward through the channel and discharged at the top of the hole. The edges are parallel to within a short distance of the extremity of the shank, where the right-hand edge is slightly reduced, so that the opposite or left-hand edge forms a cutting-shoulder S, that moves in advance of the opposite shoulder and eats its way through the wood.

A screw constructed after the above description may be used in all kinds of woodwork, near edges and other points, and in various thicknesses without any liability whatever of splitting or inj uring the material. By reason of the similarly-sized shank and stock no gradual expansion of the wood takes place, as in the gimlet-shaped screw; but the advanced end of the screw forms an opening of the same diameter of the stock and shank and an opening which is not enlarged by the farther insertion of the screw. Furthermore,-the cutting takes place only a sufficientdistance to accommodate the shank and body, the threads of the screw taking into the solid walls surrounding the orifice or opening and therefore forming atightconnection.

Having thus described my invention, what I claim is 1. A screw the bod y and shank of which are provided with a longitudinally disposed straight channel terminating at the point of the screw in a gouge-shaped bit, substantially as specified.

2. A screw the body and shank of which are provided with a longitudinal straight channel, terminating at the extremity of the shank in a gouge-shaped bit, substantially as specified.

3. A screw the body and shank of which are provided with a straight channel, terminating at the extremity of the shank in a gougeshaped bit, one of the edges or walls of the channel being cut away and leaving the oppominal shoulders of the channelbeing removed, 10 site edge to form a cutting-shoulder, substansubstantially as and for the purpose specified. tially as specified. In testimony that I claim the foregoing as 4:. A screw the body and shank of which are my own I have hereto affixed my signature in of corresponding diameter throughout their presence of two witnesses.

length, the shank terminating in a rounded JOHN ERICSON. end,and the shank and body being provided Witnesses: with a longitudinal straight channel extend- JOHN JOHNSON,

ing throughout their lengths, one of the ter- 1 JNO. G. J. HARRIS. 

